Hi,
Sadly, Office365 can't be managed via WSUS, we are confined to using cloud-updates. We need to configure Microsoft Endpoint Configuration Manager, for details, please view below official article.
Contents of the Microsoft 365 Apps client update package for WSUS
Quote: The update package that Microsoft publishes to WSUS only appears in the WSUS catalog. It doesn't contain a copy of the updated version of Office that's on the Office CDN. Instead, it contains information that Configuration Manager needs to be able to download and distribute the updated version of Office.